WASHINGTON – The freed POWs came home to heroes’ welcomes yesterday as their Army commander told how they were tortured – brutally beaten and threatened with death – in prison.

“It’s absolutely fantastic to be back home in the greatest country on Earth,” Staff Sgt. Christopher Stone beamed as he arrived in Michigan.

“I can’t tell you how thankful we are to be home and how grateful we are.”

Stone, clad in a plaid shirt and jeans, looked relaxed and happy. But his battered face and broken nose were reminders of his ordeal.

The Army revealed for the first time yesterday that despite Serb claims that the three GIs had been treated humanely in prison, the soldiers – nabbed near the Kosovo border on March 31 and freed last weekend – were beaten in the stomach and head with batons, punched in the stomach and hit in the face, feet and hands.

Maj. Gen. David Grange said the GIs were kept in solitary confinement, almost always hooded, forced to sleep on the floor or in chairs with their feet shackled and beaten if they tried to move. Most of the time they were denied use of a toilet.

“They were interrogated no less than four times … forced to read propaganda containing disinformation about NATO under threat of injury or death,” Grange said, adding that the torture was a violation of the Geneva Convention.

He said one of the three soldiers was hit in the back of the head with a baton and choked with a baton when he refused to reveal where his family lived.

The POWs, who were forced to wear Serb uniforms, were transferred to a military prison and given other clothing only when they were visited by Red Cross officials and the Rev. Jesse Jackson, who won their freedom after pleading with Yugoslavia’s president, Slobodan Milosevic.

The trio, including Staff Sgt. Andrew Ramirez of Los Angeles, who suffered broken ribs and a leg injury, and Spc. Steven Gonzales of Dallas have been awarded the Purple Heart. They flew to their home states on separate flights from Germany yesterday and are now on some well-earned leave.

“I think it’s unexpressible. It’s just great, being here … back home,” a choked-up Gonzales said in Dallas, admitting his release has been “a little bit stressful.”

His mom knew how to say it best: “It’s the best Mother’s Day gift I could ever, ever have.”

Gonzales, asked if he’ll stay in the Army and go back to the Balkans, said he’s going to give “a lot of thought as to where my future’s going to lead.”

Neither Stone nor Gonzales would discuss their treatment in prison. Asked about the daily beatings, Stone said, “I think, from the pictures, that’s obvious.” But he said his wounds “are healing very well. I’m feeling like my old self again.”

Meanwhile, President Clinton yesterday stuck to his guns – insisting NATO troops must be part of any peacekeeping force in Kosovo and vowing to stick to the “basic conditions” laid down by NATO to end the air strikes against the Serbs.